Landau's necessary density conditions for LCA groups

Landau’s Necessary Density Conditions for Lca Groups

We derive necessary conditions for sampling and interpolation of bandlimited functions on a locally compact abelian group in line with the classical results of H. Landau for bandlimited functions on R. Our conditions are phrased as comparison principles involving a certain canonical lattice.

Necessary Density Conditions for MIMO Sampling of Multiband Inputst

We consider a sampling scheme where a set of multiband input signals is passed through a MIMO channel and the outputs are sampled nonuniformly. MIMO sampling is a general scheme that encompasses various other schemes, including Papoulis’ generalized sampling and nonuniform sampling as special cases. We present necessary density conditions for stable nonuniform MIMO sampling and consistent recon...

Some Results on Necessary Conditions for Tow Quasidifferentiable Optimization Problems

New Necessary Conditions for

In this paper, we obtain several nonexistence results for abelian Hadamard diier-ence sets. In particular, we prove that there are no Hadamard diierence sets in abelian groups G = Z 2 Z 2 P , where jPj = p 2 , is odd and p is a prime congruent to 1(mod 4). Also we give a detailed proof for a connection between certain reversible Hadamard diierence sets and projective three-weight codes which wa...

Necessary Conditions for Subdivision Surfaces

Subdivision surfaces are considered which consist of tri-or quadrilateral patches in a mostly regular arrangement with nitely many irregularities. A sharp estimate on the lowest possible degree of the patches is given. It depends on the smoothness and exibility of the underlying subdivision scheme.